Lamp sealing apparatus



NOV. 18, 1941. NE r 2,262,760-

LAMP SEALING APPARATUS Filed June 28, 1940 4 Sheets-Sheet 1 FIc'. l

RALPH L ALLEN ROLAND M GARDNER INVENTORS I ATTORNEY.

1941- R. M. GARDNER EIAL 2,252,750

LAMP SEALING APPARATUS Filed June- 28, 1940 4 Sheets-Sheet 2 RALPH L ALLEN Roam M GARDNER INVENTORS ATTORNEY.

NOV. 18, 1941. R M- GARDNER ETAL 2,262,760

LAMP SEALING APPARATUS Filed June 28, 1940 4 Sheets-Sheet s BALI L. ALLEN ROLAND M GARpA/Z'R INVENTORS BYMM ATTORNEY.

NOV. 18, 1941. R, GARDNER ETAL- 2,262,760

LAMP SEALING'APPARATUS Filed June 28, 1940- 4 Sheets-Sheet 4 L f 1 j RALPH L. ALLEN 1? OLAZVD GARDWR INVENTORS BY i M ATTORNEY.

,' ping torch according to my Patented Nov. 3%, iti iiil ail Roland M. Gardner,

Allen, Beverly, Mass.

vania Corporation, Salem,

of Massachusetts Swampscott, and pin L.

assignon to Hygrade syl- Mass acorporation Application June '28, 1940, Serial No. 342,968

'80laims.

This invention relates to the sealing of vitreous vessels and, more particularly, to tipping oil exhaust tubes of electric gaseous discharge lamps.

The primary object of my invention is the tipping of! of the exhaust tubing of lamps when 1 vacuum pump, a line of Still another objectof my invention is the pro-*-.

vision of a means by which the lamp may be moved in a downward direction, so as to effect the tipping operation after sufficient heat has been applied to the tubing to cause it to start to melt.

Further objects and features of my invention will be apparent from the following specifications taken in coniunction' with the accompanying drawings in which:

Figure 1 is a side elevational view of the tipinvention;

Figure 2 is a top view of the scissors-like lower baiiie plate'with the burners and burner-shield inplace;

Figure 3 is a side view in section of the lower bailie plate showing'the burner shield and burner parts.

Figure 4 is a top assembly view of-the slide on which the torch is mounted;

Figure 5 is a perspective view 0! the saddle in which the torch proper is mounted.

Figure 6 is a rear sectional view of the tipping torch and the lamp in the heating position.

Figure 'I is a side elevational view of the tipping torch cams and the supporting frame.

Figure 8 is a front elevational view partly in section of the cams and the frame.

Similar reference characters refer to similar parts throughout the several views of the draw ings and in the specifications which follow:

In the manufacturing of electric gaseous discharge lamps, the quate tipping-oi! torch has some one. visability of exhausting these lamps in an inverted position in comparison to the exhausting position oi'incandescent lamps, the tippin -of! proved a troubleproblem of providing an adeend, runs part way Since experience has proven the adbafile plate I 1 tion is limited necessary by methods used in the incandescent lamp industry could not readily be adopted in the exhausting 0! electric gaseous discharge lamps. V

The exhausting process inthe manufacturing of electric gaseous discharge lamps is performed through an exhaust tube located in, and projecting from the center of the stem which is sealed to the bulb neck. The lamps are set into the exhausting machine by projecting the exhaust tubing of each lamp up into a port or head which, as it indexes around the machine, will successively establish the lamp in connection with a an inert gas-and such other contacts as are desired. The lamp is held in its proper position, suspended from the port, by a jaw chuck which grips the'larhp at about its mid-point, thus relieving much 'of the tension placed on the exhaust tubing whenit is clamped into the exhaust rubber oi the port or head. The bulb, having gone through the various processes necessary for properly exhausting an electric gaseous discharge lamp, is then ready to be tipped oil.

When the lamp, I, reaches a position directly behind the tipping torch, wards the exhaust tubing, 2, of the lamp. The of the torch pivots about the stud 5 as a center, to which it is connectedbys metal plate I! and saddle 28, as hereinafter described, in such a manner as to compensate for any slight variance in the vertical alignment of the tubing 2, in the line of motion of the torch. This moby the stud in the elongated slot 56. This compensating arrangement is made might be present in the flares of the lamp and/or the exhaust tubing. Even a slight variance in these parts would throw the torch and exhaust tubing'out of alignment. A channel, 0, narrowing down to the width of an exhaust tube at its baille plate, 3, from its forward extremity, thus serving as a guide in centering the torch in its proper alignment with the tubing. The lower baflie plate, 1, is a scissors-like member of two and forming a channel, 1, at its forward end, similar to the one in the top p rts 4, 4, meeting plate.

when this alignment variance has been corrected, the torch is ready to move in and encircle the tubing in the hole 8 at the apex of the tipping cone formed by the burner shields l8 and I8. Thisis accomplished by the action of the scissors-like lower baille plate, 4. A small spring 9, sensitive to the slightest tension is located at the torch moves in toreason of slight variances that;

down the middle of the top v torch will either ing or in the length of'that a point directly behind the tipping cone, 8, and is joined to the shears of the scissors-like baiile plate. When the. torch reaches that point inits forward projection where the exhaust tubing makes a contact with the outer section of the tipping cone adjacent to the channel 1, the slight force exerted thereby will cause the shears of the baflle plate 4 to pivot on the studs 51 and 58 thus opening the shears of the ballie plate 4 and allowing the tubing to enter the tipping cone. When the torch has been projected forward sufficiently to allow the tubing to enter the hole 8 in the tipping cone, the tension on the spring 9 created by the opening of the shears of the baflle plate will cause the jaws oi the lower baille plate 4 to resume their closed position, thus completely encircling the tubing in the tipping cone formed by the burner shields, l8 and I9.

Since the distance of the normal forward motion of the torch moving in, encircling the exhaust tubing until the tubing is in the tipping cone, is a predetermined one, provision must be made for irregularities in torch and the tubing'in the line of motion of the torch. It the tubing is not exactly perpendicular and exactly centered in the stem, the project itself in too far Or not far' enough in order to center the tubing in the tipping cone. To provide for this, the saddle 28 with the pin 29 held in elongated slots 30 and 3| by the cotter pins 32 and 33 is employed. Thus,

the vertical alignment of the of this type is to make sure that, at all times, the cone-like shield sections are flush with the flare and th lower surface of the lower baiiie plate is flush with the seal thereby insuring a tipping oil of the exhaust tubing below the height of the seal. Since the length ofthe normal drop taken by the torch after it has centered itself with the exhaust tubing is always the same, the burner elevation adjusting stud 24 and bolt 54 provide the variance H for the torch to either dip down by its own weight further than the ordinary length of this drop or to slacken upon this drop once the bottom surface of the lower baflle plate has dropped flush with the lamp seal.

The torch remains in this position down inside the flare long enough for the flame to start melting in the glass tubing. The torch, in a downward motion then pushes the lamp down, away from the upper extremity of theexhaust tubing a distance suflicient to accomplish the severance of the tubing. When thelamp and the torch reach this position of complete severance from the exhaust tubing, the torch moves in an up-'- ward direction to a position about A of an inch when the torch moves in to center th tubing in its tipping cone, an allowance equal to the length of the elongated slots is available to properly center such exhaust tubings as are not in exact perpendicular alignment, Thus the torch may move forward or backward on the pin 29 providing the variance equal to the length of the elongated slots 30 and 31.

An oxygen gas line l4 and a low pressure air line ll lead in to two small burners l8 and n which are located opposite each other and flush on the top of the shears of the scissors-like baflle plate 4 directly over the tipping chamber 8. Burner shield sections it and I9 are joined to lower baiiie plate 4 and the lower surface of the are conical in shape.

Once the torch has located'itself so that the exhaust tubing extends down through the tipping cone the whole torch drops down on to the top of the lamp in such a manner that the conical shaped burner shield sections l8 and I9 will slip down into'the'flare section of the stem 20 'of the lamp, and the bottom surface of the lower baiiie plate will be flush with the seal formed when the mount was sealed intothe glass envelope of the lamp. The ports 2| of the burners are so poised that the flame 22 will shoot in a downward direction, striking the exhaust tubing near the apex of the conical burner shield sections it and I9. By tipping the lamp 011' down inside in this manner, the possibility 01' an exhaust tube being tipped off at a point higher than the rim of the seal is thereby eliminated.

-Due to slight variances that'might be present in the length of diflerent pieces of exhausttubportion of the tubing projected into the exhaust rubber 23 by the operator, both of which variances would tend to vary the distance between the point on the tubing at which and the top of the seal, the burner elevation adi ung stud 24, and the bmner elevation adjusting bolt are employed as stops to provide for the torch originally centered itselfwith a lamp suspended'therefrom,

, the exhausting above the tipping seal, where it remains for a short period in order to properly anneal the tip. This annealing feature helps eliminate any strains that might be set up in the tip as a result of the tipping process. When the annealing has been completed, the torch moves in a backward and upward direction position, the machine indexes, and the next head, moves into a position directly behind the torch to be tipped oif.

The collar 25 projecting from the lower exten- 'sion of the torch and attached thereto, moves in with the torch when the torch centers itself with the lamp. and in conjunction with the spring 26, acts as a steadying rest to help stabilize the lamp in its proper position. The jaw chuck 21, clamps on to the lamp at about its mid-point and along with the clamp on the port 23 .into which the exhaust tubing is projected when the lamp is first placed on the machine, acts as the means of holding the lamp in its proper position as it indexes through the different steps in the exhausting process. 'This chuck is fixed to aframe extending down from the port or head into which the exhaust tubing. of the lamp is projected. The grip exerted by, the chuck 2'! on the lamp is suflicient to hold the lamp after the severing of the exhaust tube. However, the grip is such that it will permit the lamp to slide dOWn through the chuck a short distance when the torch exerts a downward force on the top of the lamp when tubing is being severed from the lamp. e

, The activation of the tippingtorch is provided by the action of the cams 34 and 35. These cams are connected to the cam shaft 36 which is supported by the cam frame 31 The motion of the cams l4 and 35 The slide 45, on which the whole torch is mounted, moves in to center 'itselr-.with the exhaus tltubing when the rear lever operating rod 40 moves in a downward direction thus causing these variances. The reason for an adjustment 7! the rear lever 43 to'plill in a downwarddirection back to its normal first and is ready is transmitted through the cam rollers 38 and 39 to the rear lever operating rod is attached to the frame 31. The

acce ed 3 since these two are joined by the rearlinh The slide roller :35 is attached to the slide d5 through the pin til and by its action in the elongated slot 68 helps transmit the vertical motion of the rear lever operating rod fill into the horizontal motion of the slide 65 on which, the torch is mounted. When the torch has centered itseli with the lamp and the exhaust tubing has been encircled in the tipping cone 8, the slide roller is is located at the upper end of the elongated slot. it is then perpendicular to the torch and parallel to the rear lever operating rod ill and the operating shaft 36. Thus the torch may be moved in a downward direction without having it move forward any further.

After the torch. centers itself with the lamp, the operating shaftfll drops and thus the torch drops down flush with the lamp and remains there until the tubing starts to melt in and thus the torch to which it is connected drops still further, and when it does the lamp becomes comor burners fixed to said elongated metal plate to direct a flame into said cone;

In mechanism for tipping oil the exhaust tube oi an electric lamp having a re-entrant flame intosaid shields; and meansfor impartinga reciprocating horizontal stroke to said shields and said burners, the length of said stroke in its line or motion being automatically adjustable by the location of said exhaust tube in said line of pletely severed from the exhaust tubing. The shaft then moves up slightly in order to bring I the torch up above the tipping seal for annealing purposes. Finally, the operating shaft II and the rear lever operating rod 40 both move in an upward direction the latter moving'upward at a greater rate of speed than the former in order to accomplish the rearward as well as upward motion drawing the torch back to its original first position. The spring 49, joining the rear lever 43 and the rear lever holder 50, acts as a means of maintaining the rear lever operating rod and the operating shaft, through the cam rollers attached thereto, in a continuously firm contact with the rotating cams. By reason of its position, the spring 49; exerts an inward and downward tension at all times on the rear lever operating rod and the operating shaft, thus accomplishing the desired firm cam contact. The spring 5| directly behind the stud I2 also serves as an adjusting and checking means for when the stud around said pin to a small predetermined I! on the plate II strikes the spring, the speed with which the torch is moving, in a rearward direction is slackened thereby, thus preventing the torch from moving back too far and thus have its lower extremity strike up against the operating shaft 4| or some other member of the apparatus.

What we claim is:

1. In mechanism for tipping off the exhaust tube of an electric lamp, the combination of: an'elongated metal plate; a saddle having elongated horlzontal slots; 9. pin passing through said slots and holding said plate rotatably in said saddle, said pin making a sliding fit in said slot; stops to limit the poulble rotation of said metal plate around said pin to a small predetermined amount; a slide on which said saddle is mounted; a stud fixing said saddle rotatably on said slide; means for imparting-a reciprocating horizontal stroke to said slide; means for imparting an upand-down motion to' said slide at the forward end ,of said horizontal stroke; a hello plate having a channel therein and fixed to the forward end of said elongated metal plate; a pair of cooperating ,scissors-like bame plates normally meeting under tension and in alignment with the channel in said first-mentioned baflle plate and under said first-mentioned baflle plate; a pair of burner shields, one of said shields being ata cone with asmall hole at its apex; and a pair motion.

3. The combination of claim 2 and: means for imparting an up and down motion to said burners and said shields at the forward end of the horizontal stroke. 1

i. In mechanism for tipping oil with burners the exhaust tube of an electric lamp, the som bination of: an elongated metal plate ior sup= porting said burners; a saddle having elongated horizontal slots; a pin passing through said slots and holding said plate in said saddle, said metal plate making a rotatable fit around said pin, and said pin making a sliding fit in said slot; stops to limit the possible rotation of said metal plate amount; a slide on which said saddle is mounted; a stud fixing said saddle rotatably on said slide; means for imparting a. reciprocating horizontal stroke to said slide: and means for imparting an up-and-down motion to said slide at the forward end of said horizontal stroke. l

5. In mechanism for tipping off the exhaust tube of an electric lamp having a re-entrant stem, the combination of: an elongated metal plate; a pair of cooperating scissors-like baflle plates normally meeting under tension and supported by said elongated metal plate; a pair of semi-conical burner shields, each having a central notch, one of said shields being attached to each of the scissors-like ballle plates and meeting, when the baflle plates meet, to form acone with a. small hole at its apex; a pair of sealing of! burners arranged to direct a flame into said .cone; and means for imparting a reciprocating horizontal stroke to said plate, the length of said stroke in its line of motion being automatically adjustable by the location of said exhaust tube in said line of motion. 6. The combination of claim, 5' and: means for imparting an up and down motion to said burners and said shields at the forward end of the horizontal stroke.

'1. In mechanism for tipping oi the exhaust. tube of an electric lamp having a re-entrant stem, the combination of: an elongated metal plate; a battle plate having a channel therein and fixed to the forward end of said elongated metal plate; a pair of cooperating scissors-likebaflle plates normally meeting under tension and in alignment witlrthe channel in said first mentioned baflle plate and under said first mentioned baffle plate; a pair of semi-conical burner shields each having a central notch, one of said tube of an electric lamp having a re-entrant 1 stem, the combination of a pair of semi-conical 1 burner shields each having a central notch; a pair of sealing-0H burners arranged to direct a flame into said shields; an elongated metal plate -for supporting said burners; a saddle having 1 elongated horizontal slots; a-pin passing through 4 e a r 2,262,760

-8. In mechanisni for tipping oi! the exhaust said slots and holding said plate in said saddle; Q

a slide on which said saddle is mounted; means for imparting a reciprocating horizontal stroke to saidslide; and means for imparting an upand-down motion-to said slide at the forward end of said horizontal stroke.

' ROLAND M. GARDNER.

RALPH L. ALLEN. 

